The invention relates to a system and a technique for delivering and installing an implant in living bone. Specifically, the system includes an implant and a carrier attached thereto that are packaged together and delivered to the installation site within the living bone. The system also includes a variety of tools that provide flexibility in the installation process and additional components that permit the taking of impressions during first stage surgery.
It is known to enclose sterilized dental implants in packages that will preserve sterility until opened. The packages are delivered to the clinician, who elects when and where to open the package. It is also known to include in such packages carrier devices attached to the implants which enable the implant to be manipulated without directly touching it.
Placing a dental implant in the jawbone of a patient is typically the beginning of several procedures which have been developed for providing implant-supported dentition. All procedures use components, frequently referred to as an xe2x80x9cimpression coping,xe2x80x9d for transferring to the dental laboratory information about the patient""s mouth in the area of the implant on which the dentition is to be supported. Until fairly recently, it has been the usual practice to delay this information transfer step several months after installing the implant to allow the implant to xe2x80x9cosseointegratexe2x80x9d with the host bone. The result is a two stage surgical procedure; the first stage includes the installation of the implant; the second stage involves another surgery in which the gum tissue is reopened and an impression coping is fitted to the implant to gather the needed information. Since laboratory procedures cannot begin without this information, the development of a patient""s dental prosthesis was generally delayed about three to six months while the osseointegration process occurred.
Generally, the carrier has a non-rotational engagement surface (i.e., non-circular) that a dental tool engages. When the implant has external threads, the dental tool is rotated such that the rotation imparted on the combination of the carrier and the implant screws the implant into the jawbone. In some situations, however, it is necessary to have a longer carrier because the gingiva above the jawbone is thick, such that only a smaller portion of the carrier is exposed through the gingiva. In that situation, clinicians often remove the standard carrier from the implant and install onto the implant a longer carrier to accommodate the thicker gingiva. Any time the clinician touches the implant, however, there is a risk that the sterile surfaces on the implant may become contaminated.
Recently, a protocol was developed which includes taking an impression of the patient""s mouth during first stage surgery. Immediately after the implant has been installed into its final position at the site of the jawbone, the clinician removes the carrier from the implant and installs onto the implant an impression coping. Once the impression coping is installed on the implant, the clinician then applies impression material to the region to take the impression of the site in the patient""s mouth. The impression would then allow for the development of a temporary, or possibly, a permanent dentition that would be attached to the implant after osseointegration. One of the problems associated with this new protocol is the potential for movement of the implant, which has been accurately placed into the patient""s jawbone, caused by the attachment of the impression coping.
The present invention provides for an implant delivery system that includes an implant, a carrier, and an implant screw attaching the implant to the carrier. The implant can be of a variety of types and typically includes an internally threaded bore extending along its central axis. The carrier has a through bore extending entirely therethrough in which the implant screw resides. The implant screw connects the implant to the carrier such that the lower surface of the carrier abuts the upper surface of the implant. A pair of non-circular fittings on the implant and carrier lock these two components against rotation relative to one another.
The through bore of the carrier includes a non-circular socket that is to be engaged by a correspondingly-shaped section of a coupling tool. The coupling tool is engaged by a device which imparts movement on the combination of the implant and the carrier that is necessary to install the implant into its final position within the jawbone. When the implant includes an externally threaded body, the device may be a dental handpiece that imparts rotational movement on the implant to screw it into the bone. The coupling tool can be made in a variety of lengths such that the clinician selects the appropriate length for the prevailing conditions in the patient""s mouth.
After the implant is installed in its final position, the carrier is removed through the use of a driver. The driver includes a surface which the clinician grasps, a shank extending from the grasping surface, and a guide that is connected to the shank. The guide is free to move rotationally around the shank, but is limited in its axial movement along the shank. The lower end of the shank includes a surface which is non-rotationally coupled to the implant screw. The guide includes at its lower end an engaging portion which is to be non-rotationally engaged within the socket of the carrier. During removal of the implant screw, the engaging portion of the guide is coupled to the internal socket of the carrier and the lower end of the shank is engaged within a driver socket in the implant screw. When the clinician rotates the grasping surface, the carrier is held steady on the implant while the implant screw is rotated, such that it releases the carrier from the implant. Due to the configuration of the driver, the carrier can be removed from the implant without imparting any motion whatsoever on the carrier and, therefore, the implant.
If the clinician so desires, he or she can also utilize the combination of the implant and the carrier to take an impression of the patient""s mouth during first stage surgery. An impression coping and its associated bolt can be affixed into the socket of the carrier. The impression coping has at its lower end an expandable non-rotational boss that fits within the carrier""s socket. When the bolt is threaded into an internally threaded bore within the impression coping, the boss expands outward such that it becomes press fit into the socket of the carrier. This press fit engagement provides enough retention force so that an impression can be made by the clinician without the risk of the impression coping loosening from the carrier.
The bolt associated with the impression components can include an elongated head so that the bolt and impression component act as a xe2x80x9cpick-upxe2x80x9d-type impression coping. Alternatively, a short-headed bolt can be used so that the bolt and impression component act as a xe2x80x9ctransferxe2x80x9d-type impression coping. In either case, after the impression is taken, the carrier is reattached to the impression coping using the bolt. The combination of the carrier and impression coping is then used with the impression material in the dental laboratory to develop a prosthetic tooth for the patient.
Regardless of whether the clinician chooses to take an impression of the region during first stage surgery, he or she must cover the internally threaded bore of the implant after the carrier is removed. Thus, the combination of the implant carrier and implant screw is typically packaged with a healing cap. The healing cap mates with the internally threaded bore of the implant and is placed thereon prior to suturing the gingiva.
In another embodiment, the carrier includes an internal polygonal section that is at least partially defined by a threaded surface. The threaded surface includes one or more threads making a plurality of turns on the internal portion of the carrier. While the polygonal section serves the same purpose as the non-circular socket of the previously described carrier, the threaded surface provides a structure to which various secondary components can be attached. For example, the carrier can be converted into a gingival healing abutment by the addition of a gingival healing component that screws into the threaded surface. Such a gingival component can simply be a screw that has a head that is large enough to seal the opening in the carrier, or can be a sleeve-type component that fits around the outer periphery of the carrier.